Field of the Invention
The present invention relates to a composition comprising lyophilized Lactobacilli and a plant-based food, wherein the composition is substantially free of animal products. The present invention also relates to methods of treating plant-based food by administration of a Lactobacilli and a plant medium composition. Methods of using the Lactobacilli and plant-based food composition to treat E. coli or Salmonella infection in an animal in need thereof and methods of using the Lactobacilli and plant-based food composition to reduce E. coli or Salmonella contamination in an agricultural product are also provided.
Background Art
Many individuals who are concerned with healthy living focus on eating raw vegan foods. Raw foods are preferred because cooking the food changes the biochemical characteristics of the nutrients in the food and vegan foods are desired because many of these individuals prefer their food not to have any animal products or byproducts. A raw vegan diet, when it is well-balanced, offers positive health benefits to the people who are following it; however, there is a major problem with potential pathogens developing in the food because there are no chemical preservatives present. Usually the manufacturers of raw vegan food depend on refrigeration for food pathogenic bacteria containment; however, low temperatures usually do not eliminate pathogens, rather it only keeps the pathogenic bacteria dormant. Once the food is left at room temperature or it is consumed, the temperature of the food rises creating a positive environment for pathogenic growth. This may lead to food poisoning and other serious illnesses.
In 2006, it was estimated that 31 major pathogens acquired in the United States caused 9.4 million episodes of foodborne illness, 55,961 hospitalizations, and 1,351 deaths. Scallan, E., et al., Emerging Infectious Diseases 17:7-15 (2011). Nontyphoidal Salmonella accounted for an estimated 1 million episodes of foodborne illnesses, 19,336 hospitalizations, and 378 deaths. And, Escherichia coli (E. coli) accounted for an estimated 193,800 episodes of foodborne illness, 2,421 hospitalizations, and 20 deaths.
Bacteria from the Lactobacillus family is known to have an inhibitory effect on food pathogens; however, most of these bacteria are grown on animal-based medium (such as milk or meat-based medium) since their origin is usually from an animal or human gut. Additionally, the vitality of these bacteria grown using animal-based medium usually decreases significantly in a low temperature environment because their usual environment is the body temperature of their host.
The present invention focuses on identifying specific strains of Lactobacillus among the multiple possible strains based on their natural habitat characteristics. The present invention also uses specific strains of Lactobacillus as pathogenic inhibitors for vegan foods. Previously, several strains of Lactobacillus were used for their known microbial application, namely yogurt production. In choosing a Lactobacillus strain to use as a pathogenic inhibitor for vegan foods, three criteria are considered:                Grow well in vegetable or fruit based vegan mediums in a laboratory environment—as it has to be potent and effective in vegan foods.        Survive refrigerated temperatures—as it has to survive the usual refrigeration of vegan foods that is common to manufacturing and storage practices.        Have high inhibitory potency against E. coli and Salmonella when inserted in contaminated vegan foods.        
The bacteria kingdom consists of over 70,000 species and each carry very different characteristics. Probiotics usually involve one of three genuses of bacteria: Lactobacillus, Bifidobacteria, and Streptococcus. In each of these three genuses of bacteria, there are multiple species.
For a bacterial strain to be considered useful in the present invention, the specific bacterial strain should be of plant origin and show vitality in a plant-based environment such as vegan food.
From the known population of good bacteria, Lactobacillus delbrueckii subsp. bulgaricus was identified as a bacteria for use in the present invention. Lactobacillus delbrueckii subsp. bulgaricus is found naturally on four different plants in Bulgaria: Cornus mas (Cornelian cherry), Galanthus nivalis (snowdrop), Calendula oficinalis (common marigold), and Prunus spinosa (black thorn).
To be useful in the present invention, the specific bacterial strain should survive cold temperatures. In some embodiments, the bacterial strain useful in the present invention survive at a low temperature in its natural environment.
The strain Lactobacillus delbrueckii subsp. bulgaricus GLB 44 has been identified as bio-identical to bacteria found on Galanthus nivalis (snowdrop) in a northern part of Bulgaria in the mountainous region of Staro Selo. The natural habitat for Galanthus nivalis is in a mountainous region and the strain is capable of surviving in freezing temperatures because snowdrops grow in early spring and during their growth period, the temperatures fall below freezing.
It is important to note that even though the bacterial strain GLB 44 is of a known variety, it has only been shown to be useful in association with yogurt production in milk environments and it has not heretofore been tested for its survival in different plant-based mediums. Furthermore, it has neither been tested for its ability to survive in artificially refrigerated environments nor has it been tested for its effects on E. coli or Salmonella. The present invention provides the use of this bacterial strain in compositions comprising Lactobacilli and a plant-based food wherein the composition is substantially free of animal products and methods of using these compositions.